Oliver Miles: The tawdry truth about Tony's too-tight trews

'An ambassador is an honest man, sent to lie abroad for his country'

The publication of Sir Christopher Meyer's memoir "DC Confidential" has been condemned by Jack Straw as a breach of trust, and others have warned that it will damage the Foreign Office. But the issues raised are much wider.

Ambassadors' witticisms about the tightness of prime ministers' trousers or the looseness of deputy prime ministers' vocabulary are usually consigned to the confidential files of the Foreign Office. Occasionally, as with John Phillips's famous despatch about the Muscat national anthem, they are so entertaining that they get leaked. Rarely, as in this case, they are flaunted. The most famous example is Sir Henry Wotton's joke, "An Ambassador is an honest man, sent to lie abroad for the good of his country".

Wotton was sacked by King James I, and there are of course still rules. Unfortunately these days they are so tightly drawn that they are a dead letter. To reveal that embassy crockery has the royal arms on it could be construed as a breach. There are also conventions, which are more important. It is accepted that ambassadors, like military commanders, may write their memoirs. The memoirs have to be approved by the powers that be. This is because reckless publication might put British lives or interests at risk. Meyer's book would not on past form have been approved by the Foreigtn and Commonwealth Office, but intriguingly it was approved by the Cabinet Office. To that extent the author is in the clear. Ministers and ex-ministers - Blair, Straw, Major - would be informed where appropriate, and probably have a chance to express their views.

As advisers to ministers, diplomats are like other civil servants and bound by the same rules, including the principle that advice given by officials to ministers should remain confidential. But questions of confidentiality affect us all. Lawyers, doctors, priests,social workers, employers, trade unionists, all have a duty at times to avoid a breach of trust, which implies maintaining confidentiality. The media appear at first sight to be a unique case, cast in the role of reptiles or vultures, with every interest in undermining trustworthiness. Journalists make their living by bringing information into the public domain. But they also rely as much as everyone else on trust. Good journalists have gone to prison to protect their sources. In more humdrum questions such as the protection of their reputations and the financial viability of their own companies, journalists are no different from the rest of us.

Confidentiality was taken too far in the past, notably in the Foreign Office. As the pendulum swung the other way, with the parrot cry against the "cult of secrecy", we have seen the 30-year rule replace the 50-year rule, a Freedom of Information Act, and a tendency for many in the professions including the diplomatic profession to push beyond the limits of conscience and taste. In this they have of course been egged on by the media. Has this now gone too far? If so, what can be done about it? I am pretty sure that legislation is not the answer; think of the Data Protection Act. So far as my own former profession of diplomacy is concerned, I agree with Jack Straw that Meyer has indeed gone too far. DC Confidential looks like a good read. But its publication while its story is both fresh and controversial harms the public interest. Woodrow Wilson's slogan "Open covenants of peace, openly arrived at, after which diplomacy shall proceed always frankly and in the public view" was an illusion. Diplomacy, like any serious business, requires people to express their views honestly and robustly, not looking round to see who is scribbling in his diary.

Oliver Miles is a former British ambassador to Libya